My invention relates to improvements in the performance, reliability and operation of battery powered devices, in particular battery powered night vision devices.
A night vision device (NVD), also frequently referred to as an ‘image enhancement device’, is an optical instrument that allows images to be produced in levels of light approaching total darkness. Often used by the military and law enforcement agencies, NVD's are also available to civilian users. Night vision devices were first used in World War II, and came into wide use during the Vietnam War. The technology has evolved greatly since their introduction, leading to several “generations” of night vision equipment, each having a higher performance and lower price than their predecessor.
Night-vision equipment can be split into three broad categories, any of which can also include a telescopic lens in addition to night vision capability:
1—Scopes—Normally handheld or mounted on a weapon, scopes are monocular (one eye-piece).
2—Goggles—Typically worn on the head, but can be handheld, binoculars have two eye-pieces.
3—Cameras—Most often permanently mounted wherever night vision is desired, such as around a building or property. The military mounts night vision cameras on some helicopters and other mobile equipment. Newer hand held camcorders may have night vision built right in.
Typical uses of night vision devices today include:                Military        Law enforcement        Hunting        Wildlife observation        Surveillance        Security        Navigation        Hidden-object detection        
The original purpose of night vision was to locate enemy targets at night. It is still used extensively by the military for that purpose, as well as for navigation, surveillance and targeting. Police and security often use both thermal-imaging and image-enhancement technology, particularly for surveillance. Hunters and nature enthusiasts use NVDs to maneuver outdoors at night. Many businesses have permanently-mounted cameras equipped with night vision to monitor their property and surroundings.
In reviewing this list of applications, it's evident that many involve the need for consistently high performing equipment and fool proof reliability while in operation. In other words, a failure of the equipment to deliver the enhanced images as it was designed to do, whether that failure is permanent, intermittent or even momentary, can have a big impact. A mal-function can result in something as frustrating as losing track of whatever the user was viewing, or more significantly it can result in the endangerment of property or even the safety of human life.
Enabling components of image enhancement devices start with a conventional lens, called the objective lens, which captures ambient light and some near-infrared light. The gathered light is sent to an image-intensifier tube that collects and amplifies the infrared and visible light. The result is the presentation of an image that is enhanced, and made more visible to the human eye.
The image-intensifier tube requires a power source in order to perform this amplification. In most NVDs, the power supply for the image-intensifier tube comes from small batteries such as two N-Cell or two “AA” batteries. The tube outputs a high voltage, about 5,000 volts, to the image-tube components.
The challenges of a well-designed, high performance night vision device come about as a result of how it receives the necessary electrical power to perform in combination with the conditions under which it is used. In reviewing the aforementioned list of typical uses, it can be envisioned that any in the list might involve an individual physically carrying an NVD while they are traversing through rugged terrain under extreme conditions. This will undoubtedly result in the NVD itself receiving rough treatment. The most extreme shock an NVD may experience may be that from the recoil of a rifle that it is mounted on.
The most frequently encountered problem with the proper functioning on an NVD is loss of power. When an NVD is initially turned on, it experiences a lengthy ‘boot up’ cycle before which the image enhancement function is operational. Losing power results in having to go through this lengthy ‘reboot’ of the device, during which time the image enhancement feature is not available. The original purpose of using the NVD is then not achieved because the visible detection of whatever was being focused on is lost, and the target is able to move on without detection. This loss of power can be as a result of having to change the battery due to its low charge level or it can be from the batteries being knocked about (such as from the recoil of a rifle being shot) and losing electrical continuity within the device.
Another issue of importance in NVD design for units that are not directly mounted to a building, structure or vehicle, is the overall weight of the assembly, including batteries. Having less weight to carry around is a significant issue when one is carrying and using the NVD for extended time periods, which can be the case for night vision goggles or a night vision scope mounted on a rifle, for example.
Another concern of NVD users is the battery itself. Batteries have a limited source of reserve power, can be costly, and can come in a vast variety of shapes, sizes and voltages. It is desirable to make use of a battery that has a maximum rated life span while still being portable, and standardize on as few different battery specifications (i.e. shape, size, voltage) as can be, as it is much more convenient to supply oneself with a single type of battery that is readily available, sold in bulk at a reduced price, and that can power more than 1 device. This can mean that a user does not necessarily have to carry a different set of spare batteries for each and every device they own. Rather, they can carry fewer spares, and swap out batteries only in the device(s) that may lose power during their outing.
What is required in the field of night vision devices is a design that—                ensures there is no interruption, even momentarily, in the supply of battery power once the unit is turned on, until such point as the operator deliberately turns the unit off,        maximizes the available contact surface between the power source and the device to ensure the flow of electrical power is constant and consistent,        supports the ability to utilize a source of battery power that has a maximum amount of reserve charge,        allows the option to minimize the overall weight of the night vision device/assembly,        lets the owner of several devices standardize on the batteries necessary to purchase,        supports the use of rechargeable/reusable batteries,        allows fewer spare batteries to be carried by the owner during use.        
None of the prior art discloses or addresses all of these issues which are resolved by my invention, nor do they afford the benefits specifically designed into my invention.
For example,                Hankel, et al. U.S. Pat. No. 7,417,403 discloses a device that allows a user to use a smaller battery within the battery compartment of a set of night vision goggles, while at the same time retaining the use of the original product's battery compartment cap and allowing use of the original sized battery if the user so desires, perhaps to maximize resale value of the device. The focus is on allowing the user to select a more commonly available battery size. Given that the invention reduces the size of the battery compartment it is not seen that a significantly longer battery life is achieved with the use of smaller form factor batteries. While Hankel, et al. speaks to reducing the overall weight of the device (including batteries), because of the added weight of the invention itself, and the relatively small difference in battery size feasible for use, the weight savings appear to be negligible. Neither is there any claim to improvements made in the performance of maintaining constant electrical continuity under adverse conditions (i.e. recoil from a rifle being shot), rather Hankel et al presents a design that makes use of the original electrical contact points inherent in the device as delivered from the manufacturer.        Maeshima, et al. U.S. Pat. No. 5,805,440 discloses a device that incorporates an adapter for a battery compartment, but it is made to accommodate the powering of the device by AC current which first passes through a converter to change it to the appropriate DC current.        Cornog, et al.—20030090162 presents a design that allows remote positioning of battery packs that are connected to a portable power tool. No claim is made in the design to any improvement made toward maintaining constant electrical continuity under adverse conditions (i.e. recoil from a rifle being shot), nor the use of different batteries having a longer life.        
My invention enables anyone who owns a night vision device to be assured that there will be no interruption in the supply of electrical power once the power to the device has been switched on, to use a longer life battery, to enjoy the benefits/features available from a commonly found and standardized battery source across the owner's other battery powered devices, to minimize expenses through the use of rechargeable/reusable batteries, and gives them the option of relocating the power source to realize a weight reduction in the entire assembly being carried.